> ## Documentation Index
> Fetch the complete documentation index at: https://docs.primeintellect.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# What is Lab?

> An overview of Lab, Prime Intellect's open research platform for post-training

Lab is Prime Intellect's open research platform for post-training. It unifies the [Environments Hub](/tutorials-environments/environments), Hosted Training, and Hosted Evaluations into a full-stack platform for reinforcement learning research and optimization.

The platform enables the entire lifecycle of post-training research — from large-scale agentic RL, to inference and evaluation — without needing to worry about the costs of massive GPU clusters or the details of low-level algorithm implementation.

## Core Concepts

### Environments

Lab is built around **environments**, which contain everything needed to run a model on a task:

* A **dataset** of tasks (input prompts with optional ground-truth answers)
* A **harness** for the model (tools, sandboxes, context management, multi-turn interactions)
* A **rubric** to score the model's performance (reward functions, metrics)

Environments are self-contained Python modules built with the [verifiers](https://github.com/PrimeIntellect-ai/verifiers) library. They can be used to train models with reinforcement learning, evaluate capabilities, generate synthetic data, optimize prompts, experiment with agent harnesses, and more. See [The Environment Model](/hosted-training/environment-model) for a detailed breakdown of environment types and the rollout loop.

### Environments Hub

The [Environments Hub](https://app.primeintellect.ai/dashboard/environments) is a community registry where you can browse and deploy open-source environments, or create and share your own. Environments support running evaluations with any OpenAI-compatible model endpoint, or training any supported open-weights model via Hosted Training.

The hub includes a range of pre-built environments spanning math, coding, games, search and tool use, multimodal tasks, and more — as well as validated implementations of popular benchmarks like AIME, MATH-500, and Humanity's Last Exam.

### Hosted Training

Hosted Training allows you to run large-scale RL training experiments in your own environments without managing infrastructure. Prime Intellect currently supports agentic RL with LoRA, built on the open-source [prime-rl](https://github.com/PrimeIntellect-ai/prime-rl) training library.

### Hosted Evaluations

Run evaluations against any environment directly from the web UI or CLI, using Prime Inference or your own OpenAI-compatible endpoints. Results are saved and viewable in the terminal UI or on the dashboard.

## Architecture

The platform is powered by the [prime-rl](https://github.com/PrimeIntellect-ai/prime-rl) training framework. The three key components of the architecture are:

* **Trainer** — Consumes batches and updates model weights using LoRA
* **Inference** — Serves the model via an OpenAI-compatible API with live weight updating
* **Orchestrator** — Manages environment logic, schedules rollout requests, and coordinates the training loop

For Hosted Training, each run is allocated a dedicated Orchestrator which manages environment logic, while Prime Intellect manages multi-tenant LoRA deployments for the Trainer and Inference components. This architecture allows shared hardware across runs, enabling high efficiency and per-token pricing.

## What You Can Do with Lab

| Capability                    | Description                                                                       |
| ----------------------------- | --------------------------------------------------------------------------------- |
| **RL Training**               | Train open-weights models with reinforcement learning on your custom environments |
| **Evaluation**                | Benchmark any OpenAI-compatible model against environments on the Hub             |
| **Environment Development**   | Build, test, and share environments using the verifiers library                   |
| **Synthetic Data Generation** | Generate rollout data for downstream use                                          |

## Key Libraries

Lab integrates with two core open-source libraries:

**[verifiers](https://github.com/PrimeIntellect-ai/verifiers)** — The environment framework. Provides building blocks for datasets, rubrics, tools, sandboxes, and multi-turn interactions. Environments built with verifiers are portable across local evaluation, hosted evaluation, and Hosted Training.

**[prime-rl](https://github.com/PrimeIntellect-ai/prime-rl)** — The training framework. Supports fully asynchronous distributed RL at scale with FSDP2 training and vLLM inference. Used both for self-hosted training on your own GPUs and as the backend for Hosted Training.

## Getting Access

To get started with Lab:

1. [Create a Prime Intellect account](https://app.primeintellect.ai)
2. Install the Prime CLI: `uv tool install prime`
3. Authenticate: `prime login`
4. Set up a workspace: `prime lab setup`

<CardGroup cols={2}>
  <Card title="Getting Started" icon="play" href="/hosted-training/getting-started">
    Set up your workspace and run your first environment.
  </Card>

  <Card title="End-to-End Training Run" icon="rocket" href="/hosted-training/end-to-end-run">
    Walk through a complete Hosted Training run.
  </Card>
</CardGroup>
